Electronic structure of Sm3+ ions in YAG and cubic sesquioxide ceramics

Abstract A comparative analysis of the low temperature energy level structure of Sm 3+ ion in YAG and sesquioxide (Y 2 O 3 , Lu 2 O 3 , Sc 2 O 3 ) microcrystalline ceramics, based on new and previously reported data is presented. The Stark level structure of Sm 3+ ion is discussed in terms of nephelauxetic and crystal field effects, determined by structural characteristics of the centers (of D 2 symmetry for YAG and C 2 or C 3i for sesquioxides). The Sm 3+ electronic structure of C 2 centers in sesquioxides presents some peculiarities (barycenters positions, 4 F 3/2 splitting along the series, etc.), that are correlated to J mixing effects, important for low symmetry systems and increasing from Y 2 O 3 to Sc 2 O 3 . The energy levels of Sm 3+ in centrosymmetric C 3i centers in Sc 2 O 3 , obtained by a time-resolved technique, along with the previous reported data on sesquioxides are also analyzed.